Perforator for well pipes



2 Shets-Sheet 1 .1, c. Luccous' PERFORATOR FOR WELL PIPES FiledN 27,1941 March 1943.

INVENTOR. JOHN C. [uccous 7 I fitter/lay March 30, 1943.

J. C. LUCCOUS PERFORATOR FOR WELL PIPES Filed NOV. 27, 1941 Z He 1/ 2Sheets-Sheet 2 III/II I INVENTOR.

Jan/v CI Zuccous Ht tor-nay Patented Mar. 30, 1943 UNITED STATES PATENTOFFICE PERFORATORFOR WELL PIPES JohnC. Luccous, Dallas, Tex.

Application November 27, 1941, Serial No. 420,614

1': Claims. (o1. ial-0.4)

This invention relates to new and useful improvements in perforators forWell pipes.

One object of the invention is to provide a,

means providing for accurate location of the.

perforations-in the well pipe at anydesired elevation .therein.

Aiurther object of the invention is to provide,

in a perforator of the type described, means for.

positively. disclosing whether the cutter points have been moved totheir fullyexpanded position, thus indicating that the desired'perforaations in the well pipe have been made.

Another object of'the invention is to provide,

in a perforator of the. character described, means for positively:holding the cutter points in re-.

tracted position while lowering said perforator to the desired point inthe well pipe, whichmeans isreleasable to permit operationoftheperforator when desired. 7

A still further object. of the invention is'.to provide an improvedperforator of the character described having meansfor preventing theapplication of. downward .or longitudinal movement to the cutterpointswhile. said points are expanded in cuttingposition, whereby uniformperforations. of the desired size are obtained, and also wherebyfracture or breakage of the cutter points is eliminated.

Still another object of the invention is to'provide, in aperforator ofth'eitype described, means for assuringthe securing of thesize andnumber. of perforations desired, said means limiting penetrationof thecutter points through the wall 'of the wellpipe'so that completeprojection of all cutter pointsthrough said pipe is positively secured.7

Aparticular object of the invention is to provide a perforator of thecharacter described having anchoring means for locating .saidperforatorat any desired elevation in the wellpipe and also having means forpositively securingperforations spaced from each other longitudinally-ofthe well pipe anydesired distance apart.

Another object'oi the invention is to provide a simple, positive, easilyoperable periorator which may be lowered into, operated and removed fromthe well pipe on a flexible wire or cable, and which forms taperedperforations in the well pipe, whereby plugging or clogging of suchperforations by matter carried by fluids flowing therethrough ismaterially reduced.

Additional objects and advantages of the invention will be apparent fromareading of the following description of a device constructed in Yaccordance with the invention, and reference to the accompanyingdrawings thereof, wherein:

Figure 1 is a view, partly in elevation and Figures 6 and? are enlargedhorizontal cross sectional views taken on the lines 6-6 and ll-lrespectively of Figure 2, I

Figures 8 and 9 are similar views taken onfthe lines 88 and 9,-9respectively of Figured,

Figure 10 is a view, partly in elevation and partly in section, of amodified form of the invention, and V Figure 11 is a view, partly inelevation and partly in section, showing the device of Figure 10revolved 90 degrees on its axis.

In the drawings, the numeral l5 designates an elongate cylindrical basemember having a notch l 6 formed in its upper end. Perforator knives I7are pivotally secured within said notch by means of pins !8 whichextendtransverselyof the notch through the base member and the lowerends of the knives. each knife is rounded and pivots closely adjacentthe bottom of the notch l1, so as to be additionally supported by thebase member. The perforator knives are formed with long handle portionsl9, and have chisel-pointed cutter points 29 extending laterally outwardfrom the arms at their upper ends. 1

An elongate tubular sleeve 2i telescopes the perforator knives and thebase member, and is slidably connected to said base member by means of akey pin 22 mounted in the upper end of the base, saidkey having its endsengaging within longitudinal key slots 23 formed in the wall of thesleeve. The engagement of the key pin and slots serves to limitlongitudinal movement between the base member and sleeve and to preventIt is noted that the lower end of rotation of said base member Withinsaid sleeve. Elongate Vertical windows or slots 24 are provided in thesleeve 2| and the cutter points at the upper ends of the perforatorknives are slidable longitudinally therein and expansible radiallytherethrough.

For expanding the cutter points 28, to drive them through the wall ofthe well pipe or tubing T, a cylindrical wedge member is connected tothe upper end of the sleeve 2| and extends downwardly therein. The wedgemember has longitudinally extending inclined slots 23 formed on oppositesides thereof to provide inclined wedge surfaces 21 upon which theperforator knives are adapted to slide and be radially expanded, as isclearly shown in Figures 2 and 4. Obviously, as the wedge member andsleeve are moved downwardly with relation to the cutters or knive andbase member, from the position shown in Figure 2 to the position shownin Figure 4, the inclined wedge surfaces 21 will expand the cutterpoints 21! radially outward through the windows 24 into engagement withthe wall of the well tubing. Application of sufficient force to thewedge member will then drive the cutter points through the tubing wallto form perforations therein.

The wedge member is forced downwardly by means of hammer blows deliveredby manipulation of an ordinary weight member 01' sinker bar 28 and linkjars 29 connected to the upper end of the wedge member by screw-threads.The sinker bar and jars are manipulated within the well tubing by meansof a flexible wire line or cable 3|] connected to the upper end of thesinker bar by means of a suitable wire line socket 3|. Obviously,lifting the sinker bar and jars to the position shown in Figure 1 anddropping them to the position shown in Figure 3, will impart a hammerblow to the wedge member 25 and force said wedge member downwardlybetween the perforator knives.

For holding the base member stationary to p rmit forcing the wedgemember downwardly, an anchor or stop member S is connected by means ofscrew threads to the lower end of the base member.

The anchor includes an elongate mandrel 32 having a cylindrical portion33 at its upper end. Immediately below the cylindrical portion themandrel is tapered downwardly to form a slip expanding section 34, andan annular flange 35 is provided immediately below the slip expandingsection. Below the flange 35 the mandrel has a reduced cylindrical shank36, upon which a slip carrying collar 31 is freely slidable.

Gripping elements or slips 33 having sharp gripping teeth on their outersurface are slidable on the inclined slip expanding section 34 of themandrel, and said elements have handles 39 depending therefrom. The sliphandles extend downwardly through slots 4|! formed in the flange 35, andare loosely connected to the slip carrying collar 3'! by means of theengagement of their T-shaped lower ends 4| within correspondinglyT-shaped slots 42 formed in the upper portion of the collar Bl. The sliphandles are restrained against outward displacement from the slots 42 bya band 43 which is secured in an annular groove surrounding said collar.A similar band 44 prevents outward displacement of the slip handles fromthe slots 45 in the flange 35.

The slip carrying collar 31 is slidable on the shank 35 and upwardmovement of the slips on the mandrel is limited by the engagement ofsaid collar with the under side of the flange 35. En-

gagement of the slips with the upper surface of the flange preventsfurther downward movement of the slips on the mandrel.

As will readily be seen, normally the weight of the slips and the collar3'! will move said slips to their lowermost position on the mandrel,engaging the flange 35. However, downward movement of the mandrel withrespect to the slips will move the inclined slip expanding section 34downwardly between the slips to force said slips radially outward intogripping engagement with the wall of the tubing T. Such relativemovement may be obtained by suddenly lowering the mandrel. Due to theirinertia, the slips and collar will remain substantially stationary andthe inclined section of the mandrel will move down wardly between theslips to immediately expand them to gripping engagement with the tubing.

Once the slips have engaged the wall of the well tubing, furtherapplication of downward force to the mandrel 32 tends to increase thegripping action of the slips. Thus, the anchor member is held stationaryto support the base member l5 of the perforator so that the wedge member25 may be driven downwardly to force the cutter points 20 radiallyoutward through the wall of the well tubing to form perforations Ptherein, as shown in Figures 3 and l.

The position in the well pipe at which the stop member S is set oranchored will ordinarily be determined by use of the customary measurindevice (not shown) at the surface of the well for measuring th length ofwire lowered into the well. Of course, any other suitable means might beused.

In lowering the perforator into the well pipe T, it has been found thatit is desirable that the sleeve 2| and base member l5 be held in theextended position shown in Figures 1 and 2, whereby the perforatorknives I! are held retracted. In such position the wall of the sleeve atthe lower end of the vertical window 25 enages the outer edge of theknives to move said knives inwardly to retracted position. Forreleasably holding the sleeve and base in such position, a shear pin 45extends through said sleeve and base member just below the key pin 22.Obviously, the shear pin will hold the parts in this extended positionuntil such time as said pin is fractured to permit the sleeve totelescope the base member. The pin 45 is readily sheared by jarringdownwardly upon the wedge member 25 and sleeve 2| after the stop memberS has been anchored in the well pipe. The shear pin may be readilyrenewed each time the perforator is used.

For positively indicating that the cutter points have been moved totheir fully expanded position, and, hence, that said cutter points havepenetrated the wall of the well pipe, an indicator pin 46 is securedwithin a transverse hole provided at the lower end of the base member.As is clearly shown in Figure 2, the outer ends of this indicator pinproject radially beyond the surface of the base member. Thus, when thesleeve 2| has been moved to the position shown in Figure 4, the lowerend of said sleeve will have sheared off the projecting ends of saidindicator pin. Since the sleeve 2| is moved to its fully telescopedposition (Fig. 4) when the wedge member 25 has been forced downwardly tothe position at which the cutter points 20 are fully expanded, it willreadily be seen that when the projecting ends of the indicator pin aresheared off the cutter points are indicated to have been fully expanded.

The cutter points are so dimensioned that,

upon full expansion, their :outer points will :ex tend beyond thenormal-outer "diameter :of the pipe -and,-therefore,' completepenetration of the wall of the pipe is assured Thus, disclosure that thecutter points have been fully expanded would indicate-that thedesiredperforations have been made-in the wallof the pipe.

It 'is noted that the cutter-points :20 maybe driven through the wall.of the well pipe only until the handles [9- of the knives engagethepipe just below-the cutterpoints. This-engagement of the handleswith thepipe prevents further .penetrationof the cutter points throughthewall ofthepipe. Thus,'ifone cutter point is driven through 'the wall of thepipe in advance of the-other point,- engagement'of the handle of suchadvance knife-with :the wall of the pipe preventsfurther penetrationof-that point, and the opposite cutter isthenforced through the wall ofsthe-pipe.

It-will be seen; therefore,"that the perforations formed by'means ofthis perforatorcan never be larger thanthe size formed by such maximumpenetration of the cutter points, and, also, that complete penetrationofthewall' of the pipe by both cutter points is assured.

When thewedge member -has been forced to -its=lowermost position, itslower 'end engages the-upperend of the "base member 15 and furtherdownward movement of said wedge member :and the sleeve 2l carriedthereby is prevented: This prevents the sleeve at the upper endsof'thewindows 24 from engaging the upper ends of the perforator knivesand forcing the: cutter points downwardly, whereby breakageor-shearing-of the cutterpoints isprevented. Also,-such engagementprevents-unintentional longitudinal enlargement of the perforationssuchas might result from driving the cutter points downwardly whileexpanded; thusassuring the-formation of uniform perforations ofthe-desired :size.

. To remove the 'perforator from 'the 'well .pipe T, the wireline isliftedto elevate :thesinker;

bar-.28 and link jars 29. Upward imoyementof the dam moves the wedgemember 25 and the sleeve 2l upwardly, and said-sleeve engages-thehandles IQ of the perforator knivesr-at the flowerends. of the windows24 to positively retract thecutter points'zfl from the perforations P.:F u-rtherv upward movement of the Wire-line-moves-the parts of theperforator to the position shown in Figures -1 and 2, with-the key .pin22 engaging the sleeve at thelower end :of the key slot 23 to move thebase member +5 upwardly; Upward.

movement of the base member raisesthe attached mandrel 32 of thestop;member S frombetween the slips 38, permitting;- saidslips to retractfrom gripping engagementwlth then-wall of the well pipe;'Continuedupward movement then removes the" entire device-from. thebore-- of the pipe.

A- modified form of theinvention is shown Figures l0 and 11, whereinastop member'A-is provided which is made separate from the ,per-.

forator proper andis anchored within the 'well' pipe in a slightlydifferent manner from the stop member-S of the firstform.

As is clearly shown in FigurelO, the stop in cludes amandrel I32having;an axial bore 5! Above the upper cylindrical section '33,themandrel is formed with a, retrieving necki! having-an etxernalundercut flange 52 at its upper end, and an upwardly facing-annularshoulder 53.is formed between said retrievingneck and All thecylindrical portion 33 of the mandrel.

other parts of the stop Aware identical with .and bear the same numbersasthe stop S :first described.-

The :stop member A is lowered into the well pipe and anchored therein bymeans'of a suitable'lowering tool (not shown) which .is connected to thelower end of thelink jars. The lowering tool may be any of severalsuitable types on the market, and, of itself, formsno-part of theinvention.

The stop member is anchored within the well pipe by expanding the slips38 into gripping engagement with the wall of the .well'pipebymoving themandre1l32-downwardly between said slips, .in-thesame manner as hasalready been described. When the stop has been anchored, theloweringtool (not shown) is released and removed from the bore of the pipe.

The-base member P5 of the perforatcr has a detachable'andinterchangeable skirt member 55 connected by screw threads to its lowerend,

the base member l5 of the perforator -in a stationary position.Therefore, the wedge. member 25 may be driven downwardly to fo-rce'thecutter points-of the perforator knives I! through the wall of the pipein the manner already set forth.

The length of the skirt member 55 may be varied as desired, so astoprovide for spacing the -;perforations longitudinally, within the pipe,b-y-definitely controlling the length of said skirt members theperforations may be as accurately spaced as the length of the skirtmember is controlled. The stop member A. remains set at the samelocation within the pipe while the perforator is removed and the skirtmember changed, and. upon reinsertion of vsaid perforatorin the pipetoits positionon the .stop member,- definite spacing of the perforationsat that elevation in the well'is assured. Thus, a plu-' ralit-yofuniform perforations, spaced at desired elevations in the well pipe,may be readily secured by removingthe perforator and changing the skirtsection.

After the tubing has been perforated, the perforator-is removed from thepipe and a 'suitable removing orretrieving'tool (not shown) is loweredinto the bore of said pipe to engage and pull the stop-member A from theWell. The retrieving tool (not shown) may be one of several-ty-peson-theopen market suitable for the purpose.

-Due to the chisel-point shape of the cutter points theperforations'Pformed thereby are flared outwardly as they extend inwardly fromthe.,ou-ter periphery of the pipe, and plugging or clogging ofsuchperforations by solid matter carried by the fluids flowingthereth-rough is prevented. Any' matter which enters the small outerportion of the perforations will readily pass through the larger innerportion thereof.

Manifest-1y, a perforator has been provided which may be lowered into awell pipe and oper-' ated therein to form perforations in its wall'bymeans of a flexible line or cable. Such perforator will also .-formuniform perforations .ata.

definite desired location in said pipe. Further, means has been providedfor indicating whether or not perforations have been formed in the wallof the pipe as desired. The perforator also has means for preventingbreakage of the cutter' points, both during lowering and duringperforating. Moreover, means has been provided for positively andaccurately spacing perforations at a plurality of levels within the wellpipe. Likewise, the perforator may be used with various suitable typesof stop members, either attached to the perforator or independentlyanchored within the well pipe.

It is particularly to be noted that the perforators are adapted to belowered into, operated in and removed from a well pipe under pressure,that is, in wells wherein the well fluid pressure is present within saidpipe during said operations. For such use, the flexible line would be asolid steel wire measuring line, common to the oil fields, and theperforator would be lowered into the well pipe with the upper end ofsaid pipe closed by a stuffing box (not shown) which would seal aroundthe solid steel line to prevent escape of the well pressure fluids.

The above description of the invention is explanatory only, and changesin details of the constructions illustrated may be made by those skilledin the art, within the scope of the appended claims, without departingfrom the spirit of the invention.

What I claim and desire to secure by Letters Patent is:

1. A well pipe perforator including, a base member having means forreleasably anchoring it in a stationary position within a well pipe,elongate perforator means having its lower end swingably supported bythe base member and having a perforating element at its upper end, anexpanding member for engaging the upper end of the perforator means tomove the perforating element to perforating position, and a sleevemember telescoping the perforator means and base member and having meansfor positively retracting the perforator element from perforatingposition.

2. A well pipe perforator including, a base member, releasable meansengageable with the wall of a well pipe for positively anchoring saidmember in a stationary position at any desired level in said well pipe,perforator means supported by said base member, and means for forcingsaid perforator means outwardly through the wall of the well pipe toform perforations therein, said forcing means engaging the base memberto limit the application of outward force to said perforator means bysaid forcing means.

3. A well pipe perforator including, a base member, perforator meanssupported by the base member, means for forcing the perforator meansoutwardly through the wall of a well pipe to form perforations therein,and anchoring means for engaging the wall of the well pipe to positivelysupport the base member at any desired level in the well pipe to permitformation of perforations at such level, said anchoring means beingreleasable and movable either upwardly or downwardly from the level ofthe original perforations to a new level for supporting said base memberto permit perforating at such new level.

4. A well pipe perforator including, a base member, anchoring means forsupporting said base member at any desired level within a well pipe,movable perforator cutters carried by the base member, forcing means forexpanding said cutters to form perforations in the wall of the wellpipe, and frangible means for preventing said forcing means fromprematurely expanding the perforator cutters.

5. A well pipe perforator including, a member having means for anchoringit in a stationary position in a well pipe, perforator elementssupported by said member, means operable to force the perforatorelements outwardly through the wall of the well pipe to formperforations therein, and a member engageable by said forcing meansproviding positive recording means for indicating that the perforatorelements have been forced outwardly sufficiently to form suchperforations.

6. A well pipe perforator including, a member having releasable meansengageable with the wall of a well pipe, means for anchoring it in astationary position in said well pipe, perforator elements supported bysaid member, means operable to force the perforator elements outwardlythrough the wall of the well pipe to form perforations therein, andmeans interposed between the support member and perforator elementsproviding for positively spacing perforations at a plurality of levelslongitudinally within the well pipe.

'7. A well pipe perforator including, a base member having means foranchoring it in a stationary position within a well pipe, elongateperforator knives having their lower ends pivotally secured to andsupported by said base member, a wedge member having inclined surfacesupon which the upper ends of the perforator knives are slidable so as tobe expanded to perforating position thereby, and a sleeve membertelescoping the perforator knives and having means for positivelyretracting said knives from perforating position.

8. A well pipe perforator including, a base member having means foranchoring it in a stationary position within a well pipe, elongateperforator knives having cutter points at their upper ends and havingtheir lower ends pivotally secured to and supported by said base memher,a wedge member having inclined surfaces upon which the upper ends of theperforator knives are slidable so as to be expanded to perforatingposition thereby, a sleeve member telescoping the perforator' knives andhaving windows through which the cutter points of said knives areexpansible, means for positively retracting said knives from perforatingposition, and means for releasably holding said perforator knives inretracted position.

9. A well pipe perforator including, a base member having means foranchoring it in 'a stationary position within a well pipe, elongateperforator knives having cutter points on their upper ends and havingtheir lower ends pivotally secured to and supported by the base memher,a wedge member having inclined surfaces upon which the upper ends of theknives are slidable so as to be expanded to perforating positionthereby, and means for indicating that the cutter points have beensufficiently expanded to form the desired perforations.

10. A well pipe perforator including, a base member, means for anchoringsaid base member in a stationary position within a well pipe, elongateperforator knives having cutter points at their upper ends and havingtheir lower ends pivotally secured to and supported by the base' ber toexpand the cutter points to perforating position, said wedge memberbeing arranged to abut the upper end of the base member to limit theapplication of outward force upon the cutter points and to prevent theapplication of downward force to said cutter points.

11. A well pipe perforator including, a base member, elongate perforatorknives having cutter points on their upper ends and having their lowerends pivotally secured to and supported by said base member, a wedgemember having inclined surfaces upon which the upper ends of theperforator knives are slidable so as to be expanded to perforatingposition thereby, and anchoring means for supporting the base member ina stationary position at any desired level in a well pipe to permitperforating the wall of such pipe at that level, said anchoring meansbeing movable upwardly or downwardly from the level of the originalperforations to a new level for supporting said base member to permitperforating at such new level.

12. A well pipe perforator including, a base member, elongate perforatorknives having cutter points on their upper ends and having their lowerends pivotally secured to and supported by said base member, a wedgemember slidably connected to the base member and having inclinedsurfaces upon which the upper ends of the perforator knives are slidableso as to be expanded to perforating position thereby, and separateanchoring means for supporting the base member in a stationary positionat any desired level within a well pipe to permit perforating the wallof the pipe at such level, said anchoring means being removable from thewell p1pe.

13. A well pipe perforator including, a base member, elongate perforatorknives having cutter points on their upper ends and having their lowerends pivotally secured to and supported by said base member, a wedgemember slidably connected to the base member and having inclinedsurfaces upon which the upper ends of the perforator knives are slidableso as to be expanded to perforating position thereby, separate anchoringmeans for supporting the base member in a stationary position at anydesired level within a well pipe to permit perforating the wall of saidpipe at such level, and detachable and interchangeable spacer meanscarried by the base member and interposed between said base member andthe anchoring means for positively spacing perforations at a pluralityof levels longitudinally within the well pipe.

14. A well pipe perforator including, .a base member, means foranchoring said member at any desired level within a well pipe, elongateperforator knives having cutter points at their upper ends and havingtheir lower ends pivotally secured to and supported by the base member,a wedge member slidably connected to the base member and having inclinedsurfaces upon which the upper ends of the knives are slidable andmovable toward the base member to expand the cutter points toperforating position, a sleeve member carried by the wedge member andtelescoping the perforator knives and having windows through which thecutter points of said knives are expansible, means on the sleeve forengaging the knives to retract the same from perforating position uponupward movement of said sleeve, means for releasably holding said sleevein position retracting said perforator knives, and means carried by thebase member for indicating that the cutter points have been sufficientlyexpanded to perforate the Wall of the well pipe.

15. A well pipe perforator including, a base member, means for anchoringsaid base member at any desired level within a Well pipe, elongateperforator knives having cutter points at their upper ends and havingtheir lower ends pivotally secured to and supported by the base member,a wedge member slidably connected to the base member and having inclinedsurfaces movable toward the base member for expanding the cutter pointsto perforating position, said wedge member being adapted to engage theupper end of the base member to prevent down- Ward movement of thecutter points and limit the outward expansion thereof, a sleeve carriedby the Wedge member and telescoping the perforator knives, means on saidsleeve for positively retracting said knives upon movement of saidsleeve away from the base member, and means for releasably holding thesleeve in position retracting said perforator knives.

16. A well pipe perforator including, a base member having releasablemeans for engaging the wall of a well pipe to anchor it in a stationaryposition within said pipe, elongate perforator knives having projectingcutter points on their upper ends and having their lower ends swingablysupported by the base member, a wedge member for engaging and expandingthe upper ends of said knives, said knives having an upper portionadapted to engage the wall of the well pipe to prevent excessivepenetration of such wall by the cutter point thereon, whereby when anyone cutter point has fully penetrated the wall of the pipe theengagement of such upper portion with said wall provides a stop andsupport to cause the wedge member to force the other cutter pointsoutwardly through the wall of the pipe to assure perforation thereof byall cutter points.

17. Awell pipe perforator including, a base member having means forreleasably anchoring it in a stationary position within a well pipe,elongate perforator means having its lower end swingably supported bythe base member and having a perforating element at its upper end, anexpanding member for engaging the upper end of the perforator means tomove the perforating element to perforating position, a sleeve membercarried by the expanding member and telescoping the perforator means andbase member and having means for positively retracting the perforatorelement from perforating position, and recording means engageable bysaid sleeve for positively indicating that said perforator element hasbeen fully expanded.

JOHN C. LUCCOUS.

